146 lines
5.1 KiB
Plaintext
Executable File
146 lines
5.1 KiB
Plaintext
Executable File
.\" dhcrelay.8
|
|
.\"
|
|
.\" Copyright (c) 1997 The Internet Software Consortium.
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\"
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\" 3. Neither the name of The Internet Software Consortium nor the names
|
|
.\" of its contributors may be used to endorse or promote products derived
|
|
.\" from this software without specific prior written permission.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE INTERNET SOFTWARE CONSORTIUM AND
|
|
.\" CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
|
|
.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
|
|
.\" MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
.\" DISCLAIMED. IN NO EVENT SHALL THE INTERNET SOFTWARE CONSORTIUM OR
|
|
.\" CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
.\" SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
.\" LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
|
|
.\" USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
|
.\" ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
|
.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
|
|
.\" OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" This software has been written for the Internet Software Consortium
|
|
.\" by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
|
|
.\" Enterprises. To learn more about the Internet Software Consortium,
|
|
.\" see ``http://www.isc.org/isc''. To learn more about Vixie
|
|
.\" Enterprises, see ``http://www.vix.com''.
|
|
.TH dhcrelay 8
|
|
.SH NAME
|
|
dhcrelay - Dynamic Host Configuration Protocol Relay Agent
|
|
.SH SYNOPSIS
|
|
.B dhcrelay
|
|
[
|
|
.B -p
|
|
.I port
|
|
]
|
|
[
|
|
.B -d
|
|
]
|
|
[
|
|
.B -q
|
|
]
|
|
[
|
|
.B -i
|
|
.I if0
|
|
[
|
|
.B ...
|
|
.B -i
|
|
.I ifN
|
|
]
|
|
]
|
|
.I server0
|
|
[
|
|
.I ...serverN
|
|
]
|
|
.SH DESCRIPTION
|
|
The Internet Software Consortium DHCP Relay Agent, dhcrelay, provides a
|
|
means for relaying DHCP and BOOTP requests from a subnet to which
|
|
no DHCP server is directly connected to one or more DHCP servers on other
|
|
subnets.
|
|
.SH OPERATION
|
|
.PP
|
|
The DHCP Relay Agent listens for DHCP requests on all interfaces
|
|
attached to a host, unless one or more interfaces are specified on the
|
|
command line with the
|
|
.I -i
|
|
flag.
|
|
.PP
|
|
When a query is received, dhcrelay forwards it to the list of DHCP
|
|
servers specified on the command line. When a reply is received, it
|
|
is broadcast or unicast on the network from whence the original
|
|
request came.
|
|
.PP
|
|
It is possible to specify a set of interfaces on which dhcrelay will
|
|
listen, so that if dhcrelay is connected through one interface to a
|
|
network on which there is no DHCP server, but is connected on another
|
|
interface to a network on which there is a DHCP server, it will not
|
|
relay DHCP and BOOTP requests from the network on which the server
|
|
exists to that server. This is an imperfect solution.
|
|
.SH COMMAND LINE
|
|
.PP
|
|
The names of the network interfaces that dhcrelay should attempt to
|
|
configure may be specified on the command line using the
|
|
.I -i
|
|
option. If no interface names
|
|
are specified on the command line dhcrelay will identify all network
|
|
interfaces, elimininating non-broadcast interfaces if possible, and
|
|
attempt to configure each interface.
|
|
.PP
|
|
If dhcrelay should listen and transmit on a port other than the
|
|
standard (port 67), the
|
|
.B -p
|
|
flag may used. It should be followed by the udp port number that
|
|
dhcrelay should use. This is mostly useful for debugging purposes.
|
|
If the
|
|
.B -p
|
|
flag is specified, the relay agent will transmit responses to clients
|
|
at a port number that is one greater than the one specified - i.e., if
|
|
you specify
|
|
.B -p
|
|
67, then the relay agent will listen on port 67 and transmit to port
|
|
68. Transmissions to servers will be sent to the same port number
|
|
that it specified in the
|
|
.B -p
|
|
flag.
|
|
.PP
|
|
Dhcrelay will normally run in the foreground until it has configured
|
|
an interface, and then will revert to running in the background.
|
|
To run force dhcrelay to always run as a foreground process, the
|
|
.B -d
|
|
flag should be specified. This is useful when running dhcrelay under
|
|
a debugger, or when running it out of inittab on System V systems.
|
|
.PP
|
|
Dhcrelay will normally print its network configuration on startup.
|
|
This can be annoying in a system startup script - to disable this
|
|
behaviour, specify the
|
|
.I -q
|
|
flag.
|
|
.PP
|
|
The name of at least one DHCP server to which DHCP and BOOTP requests
|
|
should be relayed must be specified on the command line.
|
|
.PP
|
|
.SH SEE ALSO
|
|
dhclient(8), dhcpd(8), RFC2132, RFC2131.
|
|
.SH AUTHOR
|
|
.B dhcrelay(8)
|
|
has been written for the Internet Software Consortium
|
|
by Ted Lemon <mellon@fugue.com> in cooperation with Vixie
|
|
Enterprises. To learn more about the Internet Software Consortium,
|
|
see
|
|
.B http://www.vix.com/isc.
|
|
To learn more about Vixie
|
|
Enterprises, see
|
|
.B http://www.vix.com.
|
|
.PP
|